1. Field of the Invention
This invention relates to a touch-sensing display device and a touch-sensing module thereof, specifically to a borderless touch-sensing display device and a touch-sensing module.
2. Description of the Prior Art
Flat display devices are now the mainstream in display devices. Electronic products such as home television, monitors of personal computers and laptops, screens of mobile phones and digital cameras are now extensively using flat display devices. As more and more consumers have the demand for flat display device with ease of control, aesthetic appearance, and multi-functions, touch-sensing liquid crystal panels are now becoming a mainstream in flat display devices.
Due to the frame of the liquid crystal panel, images cannot be displayed at the location where the frame is disposed. In order to increase the display area of the liquid crystal panel and to achieve a borderless appearance of the liquid crystal panel, a lens layer with a Fresnel lens structure is conventionally disposed in the liquid crystal panel. In this way, the lens layer can magnify the images from the liquid crystal panel and conceals the frame of the liquid crystal panel to achieve a visual effect that a portion of the liquid crystal panel can have a borderless appearance.
FIG. 1 is an exploded view of a conventional touch-sensing display device 10. The conventional touch-sensing display device 10 includes a lens layer 20, a display module 30 and a touch-sensing module 40, wherein the touch-sensing module 40 further includes an upper sensing sheet 50 and a lower sensing sheet 60. As FIG. 1 shows, the touch-sensing module 40 and the lens layer 20 are disposed on the display module 30 while the touch-sensing module 40 is disposed between the display module 30 and the lens layer 20. The lens layer 20 is a lens having a Fresnel lens structure. Due to the sealant 31 of the display module 30, images cannot be displayed at the location where the sealant 31 is disposed. In order to increase the display area of the display module 30 and to achieve a borderless appearance of the display module 30, the lens layer 20 is disposed on the display module 30 to magnify the images generated by the display module 30 and conceals a portion of the display module 30 not capable of displaying images, i.e., where the sealant 31 is disposed. In this way, the conventional touch-sensing device 10 can have a borderless appearance.
As FIG. 1 shows, an upper conductive film 51 and a lower conductive film 61 are disposed on the upper sensing sheet 50 and the lower sensing sheet 60, respectively. Two upper conductive lines 52 and two lower conductive lines 62 are disposed on two opposite sides of the upper sensing sheet 50 and the lower sensing sheet 60. Two ends of the upper sensing sheet 51 are electrically connected to the upper conductive lines 52, wherein a fixed voltage is applied across the upper conductive lines 52 to create a uniform electric field between the upper conductive lines 52. Similarly, a fixed voltage is applied across the lower conductive lines 62 to create a uniform electric field between the lower conductive lines 62. When a medium such as finger or pen touches the touch-sensing module 40, the conductive films 51, 61 of the touch-sensing module 40 will contact each other causing a voltage drop due to short circuit. The upper conductive line 52 detects the voltage of the lower conductive film 61 at the touch point via the upper conductive film 51 and then transmits the voltage to a backend processor 500. The backend processor 500 has a software-assisted function and can be disposed on a printed circuit board or a personal computer. Alternatively, the backend processor 500 can be connected to a flexible circuit board 53 as shown in FIG. 1 and then to other external devices for further processing. In different embodiment, the backend processor 500 can also be connected to the upper conductive line 52 in order to receive voltage signals directly; in this way, the flexible circuit board 53 can be omitted. Similarly, the lower conductive line 62 detects the voltage of the upper conductive film 51 at the touch point via the lower conductive film 61 and transmits the voltage to the backend processor 500. The backend processor 500 will then calculate the coordinate of the touch point after receiving the voltage signals from the conductive lines 52, 62.
As FIG. 1 shows, the lens layer 20 is disposed outside the touch-sensing module 40 as an add-on, and therefore the lens layer 20 will inevitably increase the overall thickness of the touch-sensing display device 10. Furthermore, the touch-sensing function and the relative sensitivity of the touch-sensing module 40 will be influenced by the lens layer 20. In addition, the upper conductive line 52 and the lower conductive line 62 are perpendicular to each other and are both disposed at the edge of the conductive films 51, 61. Therefore, the conductive lines 52, 62 will inevitably conceal part of the display area of the display module 30 increasing the difficulty in designing a borderless appearance. In other words, the sealant 31 and the display module 30 concealed by the conductive lines 52, 62 will decrease in the available display area. Currently, the market demands for thinner touch-sensing mobile device with a borderless appearance. Therefore, one of the current difficulties in display device manufacturing is to create a borderless display module with touch-sensing function and without increasing the overall thickness of the display device.